This invention relates to railcars. One application of the invention illustrated and described herein is a railcar suitable for intermodal or "piggyback" service in which a truck trailer is transported over long distances by railroad and then delivered locally at the end of the line by truck. This type of service also is referred to as trailer-on-flatcar (TOFC) service. The railcar of this invention, however, may be used to transport containers or other lading. Container service is referred to as container-on-flatcar (COFC) service.
TOFC rail service heretofore has not been extended to many areas in which existing tunnel and bridge clearances are insufficient to permit navigation of conventional 13 feet-6 inch high highway trailers. In the Northeast corridor of the United States in and around New York City, for example, maximum clearances correspond to the American Association of Railroads Clearance Plate "B", maximum vertical clearance being about 15 feet-6 inches and only 14 feet-8 inches for trailer-on-car widths of up to 8 feet-6 inches. Prior flatcars are unable to navigate conventional highway trailers through such clearances, even when equipped with special non-standard 28 inch wheels. Consequently, most TOFC traffic heretofore has been restricted to dedicated height clearance routing so that, as an example, virtually no freight between the Southern United States and the Northeast corridor is moved by TOFC service north of Washington, D.C. Most shippers in this area, therefore, send their goods the entire distance by truck, rather than convert from TOFC to highway service at some point during the trip. Similarly, such traffic destined for the New York City and New England areas from Chicago and the Midwestern area of the United States presently is unloaded in Northern New Jersey and trucked across the Hudson River by highway bridges to New York City, Long Island and up into the New England area. This preference for highway service produces undesirable energy waste, pollution, noise and excess traffic congestion in and around the areas affected. It further tends to increase freight rates and therefore produces an adverse economic impact upon those areas which discourages businesses from locating or remaining in those areas and encourages them to relocate elsewhere.